1. Field of the Invention
The present invention relates to a capping mechanism for an ink jet print head which is mounted for movement with the ink jet print head. More particularly, a capping mechanism according to the present invention is slidably mounted directly on the ink jet print head and is slidable relative to the ink jet print head between a capped position which protects ink ejection nozzles of the ink jet print head and an uncapped position in which the nozzles are uncapped and free to eject ink onto a recording medium.
2. Description of the Related Art
In recent years, ink jet printers have become popular because of their ability to form high quality print images at a low cost. Printers of this type form images by ejecting small droplets of ink through small ink ejection nozzles of the print head as the print head is moved across a recording medium. The ejection of ink droplets is controlled so as to form desired characters, numbers, and symbols on the recording medium.
Because liquid ink is always ready for ejection from the ink ejection nozzles, if printing is not performed for a certain period of time, such as five or ten seconds, the ink may dry sufficiently so as to clog the nozzles. Accordingly, conventional ink jet printers provide a capping mechanism which caps the ink ejection nozzles during quiescent periods when printing is not taking place so as to prevent the nozzles from clogging.
Conventional systems mount the capping mechanism at the left-most end of the print head's travel. However, because a print position indicator is normally attached to the ink jet print head, when the ink jet print head is capped at the left-most end of its travel, the print position indicator cannot indicate the next print position.
Furthermore, because a separate capping mechanism is provided, the size of the printer is unduly increased, and complex control means are needed to coordinate capping of the print head with the operation of the capping mechanism.
Thus, there is a need for a ink jet printer with a simple and compact capping mechanism that permits a print position indicator to indicate the next print position regardless of whether the print head is capped or uncapped.